150 Health Problems from Mosquitoes
Other methods used in community mosquito control programs include:
• Breeding fish that eat mosquitoes. The Central American mosquito fish,
South American guppies, African tilapia, carp, and other fish can
be used to control mosquitoes. These fish have
different common names in different places,
but are often called “mosquito fish.”
• Make sure water flows and fields drain
by restoring natural waterways,
making drainage channels to let
water move, and filling in unused
irrigation trenches and ponds. Drain
rice paddies once a week for 2 or 3 days
to kill young mosquitoes without harming
rice production.
• Plant trees to provide homes for birds, bats,
and other natural helpers in mosquito
control. Neem trees from Africa and
India keep mosquitoes away and the
leaves can be used as medicine.
Using insecticides
Where mosquitoes breed only part of the year, they can be quickly destroyed
with insecticides. In the past, the pesticide DDT was widely used to kill
malaria mosquitoes, and was sprayed outdoors over mosquito breeding sites.
But DDT is a poison that does great harm to people and animals, causing
cancer and birth defects (see Chapter 16). DDT can travel great distances in
the air and in water, and stays in the environment for many years, becoming
more dangerous over time. Because of this, community prevention activities
and less toxic insecticides are now recommended in most countries.
One type of insecticide, called pyrethrins, causes less long-term harm to
people, animals, and the land. Another advantage of pyrethrins over DDT or
malathion (another common but harmful pesticide) is that much less is needed
to spray the same amount of space.
Pyrethrins do not collect in the environment. But they are toxic when people
are exposed to them, and must be used with care. Pyrethrins irritate the skin
and eyes, and cause rashes and difficulty breathing. Avoid direct contact
with this insecticide, especially children and women who are pregnant or
breastfeeding. Pyrethrins are very toxic if they get into water sources.
Never use pyrethrin products near waterways or ponds.
A Community Guide to Environmental Health 2012